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为进一步拓展显微傅里叶红外光谱(FTIR)技术在有机地球化学研究中的应用,以准噶尔盆地下二叠统风城组碱湖相含油气系统为例,开展了沉积有机质的生烃研究。结果表明,7组红外官能团具有指征意义,并据此提出3个红外结构新参数,即A指数(A2 920/A3 600)、B指数(A2 920/A1 460)和C指数(A1 140/A1 600)。A指数揭示盐岩区烃源岩具有更高的生烃潜力,B指数揭示可能存在热液流体影响导致盐岩区有机质具有异常的热演化,而C指数表明从边缘区到盐岩区,随盐度的升高,有机质的分子聚合受到影响。据此,位于沉积中心的盐岩区油气勘探潜力较大,尽管在深层可能仍存在轻质原油。这些认识为区域油气勘探提供了新的参考资料,展示了FTIR技术能为传统的有机地球化学研究提供补充,具有广阔的应用潜力。 相似文献
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实验研究了低压环境下固着盐水液滴在不同基底表面(铜、载玻片和聚四氟乙烯)的蒸发析晶过程,分析了表面性质和环境压力的影响。结果表明,低压环境下易在接触线处析出白色盐晶。铜表面由于表面能较大,接触面上覆盖盐晶体,液滴蒸发过程接触直径几乎不变,接触角逐渐减小。在载玻片表面,当环境压力较高时,液滴蒸发造成接触线收缩,伴随盐晶体的生长和移动接触角波动。在聚四氟乙烯表面,接触面处易产生气泡,气泡的生长和爆裂导致接触角明显波动。Pe数可以揭示液滴蒸发过程外部传质扩散和内部离子扩散的相对大小。研究成果有助于指导海水淡化的工业应用。 相似文献
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Enrique Castillo Aida Calviño Santos Sánchez-Cambronero María Nogal Ana Rivas 《Computers & Operations Research》2013
In this paper we deal with the travel time reliability PUE (probabilistic user equilibrium) problem studied by Lo et al. (2006) [12] and Nie (2011) [15] and we propose an alternative model that assumes a location-scale family for the path travel times, whose means and variances are evaluated in terms of link travel times. This avoids the use of the central limit theorem and convolutions providing a flexible and simple alternative. Contrary to the most existing models that require path enumeration or an iterative method to add paths sequentially, we present a percentile system optimization in its two versions: with and without path enumeration. Two examples of applications, one of them real, are used to illustrate the power of the proposed method. The cpu times required to solve the problem seem reasonable. In addition, we answer an open question raised by Nie (2011) [15] about the permutability of percentiles and partial derivatives of route travel times with respect to route flows. A family of counterexamples is given to demonstrate that the two operations: (a) obtain percentiles and (b) partial derivation of route travel times do not commute. Finally, to reproduce the trial-and-error sequence followed by users when selecting paths, we also present an algorithm that simulates this iterative process and shows that the final long-term user behavior coincides with PUE (probabilistic user equilibrium) problem resulting from some existing models. 相似文献
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Jaime Bonachea Martín A. Hurtado Mario da Silva José L. Cavallotto Osni J. Pejon Maria Angélica de O. Bezerra Victoria Rivas Gema Fernández 《The Science of the total environment》2010,408(13):2674-2695
An analysis of geomorphic system's response to change in human and natural drivers in some areas within the Río de la Plata basin is presented. The aim is to determine whether an acceleration of geomorphic processes has taken place in recent years and, if so, to what extent it is due to natural (climate) or human (land-use) drivers. Study areas of different size, socio-economic and geomorphic conditions have been selected: the Río de la Plata estuary and three sub-basins within its watershed. Sediment cores were extracted and dated (210Pb) to determine sedimentation rates since the end of the 19th century. Rates were compared with time series on rainfall as well as human drivers such as population, GDP, livestock load, crop area, energy consumption or cement consumption, all of them related to human capacity to disturb land surface. Data on river discharge were also gathered. Results obtained indicate that sedimentation rates during the last century have remained essentially constant in a remote Andean basin, whereas they show important increases in the other two, particularly one located by the São Paulo metropolitan area. Rates in the estuary are somewhere in between. It appears that there is an intensification of denudation/sedimentation processes within the basin.Rainfall remained stable or varied very slightly during the period analysed and does not seem to explain increases of sedimentation rates observed. Human drivers, particularly those more directly related to capacity to disturb land surface (GDP, energy or cement consumption) show variations that suggest human forcing is a more likely explanation for the observed change in geomorphic processes. It appears that a marked increase in denudation, of a “technological” nature, is taking place in this basin and leading to an acceleration of sediment supply. This is coherent with similar increases observed in other regions. 相似文献
109.
针对无法获得可靠羽流流向信息不利于实现羽流追踪的问题,提出了一种基于决策树的羽流追踪移动机器人自主决策方法。该方法通过移动机器人两侧的浓度传感器采集到的浓度信息,利用追踪的行为规则建立决策树模型,获得行为决策信息,使机器人高效地追踪到羽流并精确地定位。由于浓度变化关系蕴含了羽流的流向及流速信息,从而取代了传统方法中流向及流速传感器。在扩散环境下,通过移动机器人羽流追踪实验,实现了良好的源定位效果。 相似文献